Contactless connector, contactless connector system, and a manufacturing method for the contactless connector

ABSTRACT

The invention relates to a contactless connector ( 100 ), a system including the contactless connector ( 100 ) and a corresponding mating connector ( 200 ), and a manufacturing method for the contactless connector. In order to enable the contactless connector ( 100 ) to transmit/receive power to/from the corresponding mating connector ( 200 ), the invention suggest providing at the contactless connector an inner ferrite element ( 102 ) and an inductive coupling element ( 110 ) arranged to at least partially surround the inner ferrite element. An outer ferrite element ( 107 ) of the contactless connector is arranged to at least partially surround the inductive coupling element ( 110 ), wherein a front end ( 108 ) of the outer ferrite element ( 107 ) facing the mating ( 101 ) end of the contactless connector is recessed in an axial direction of the contactless connector with respect to a front end ( 103 ) of the inner ferrite element ( 102 ) facing the mating end. A rear end ( 109 ) of the outer ferrite element ( 107 ) is magnetically connected to a rear end ( 104 ) of the inner ferrite element ( 102 ). An inductive coupling support element ( 601 ) is arranged around the inner ferrite element ( 102 ). The inductive coupling element is a wire wound around the inductive coupling support element ( 6019  to form a coil comprising a plurality of coil windings ( 115 ). The inductive coupling support element ( 6019  comprises an outwardly extending intermediate disc that divides the coil windings ( 115 ) into a first and a second coil winding section. The intermediate disc ( 602 ) has a slot ( 603 ) forming a coil wire passageway through which the coil wire is routed.

BACKGROUND

The invention relates to a contactless connector for inductivelyconnecting to a corresponding mating connector, a contactless connectorsystem comprising both connectors, and a manufacturing method for thecontactless connector. In particular, the invention provides acontactless connector that includes an inner ferrite core and a coilwound around same. Further, an outer ferrite element is provided thatsurrounds only parts of the coil. The arrangement of coil and ferriteelements allows to inductively forward/receive electric power to/from amating contactless connector.

Generally, the invention relates to contactless connectors for inductivepower transmission. Contactless power connectors are widely utilized fortheir various advantages over conventional power connectors, namely fore.g. a higher resistance to contact failures, an unlimited number ofmating cycles, a low wear and tear, prevention from electric shocks,sparks and current leaks and their operability under dirty or harshenvironments.

Specifically, contactless connectors for power transmission may be usedin a variety of industrial devices such as, for instance, roboticstechnology, rotary applications and molding equipment. Such contactlessconnectors are required to be operable under hostile environmentalinfluences, to resist a high amount of wear and tear during the matingcycles or may be used for power transmission in humid, explosive orcombustible environments.

Known configurations of contactless power connector systems allow fortransmission of electrical power between a contactless connector and amating connector.

However, in case of inductively transmitting a higher power level, aconsiderable amount of heat has to be taken into account which isgenerated due to e.g. eddy current. Heat dissipation is thus animportant aspect, which however results in a need for appropriatehousing materials. Therefore, the outer housing may be of metal, whichresults in parts of the magnetic field lines tending to flow through themetal housing. Consequently, those field lines inside the housing leadto additional losses. Overall, due to the power losses at the inductiveconnector, the power transmission decreases.

Moreover, known wireless power connectors require a precise alignment inview of the mating connector part.

Hence, there is a need for an improved contactless connector whichremedies the afore-mentioned disadvantages.

SUMMARY

The object underlying the present invention is to propose a contactlessconnector and a contactless connector system which allows for reducedsensitivity to misalignment between a contactless connector and a matingconnector in the mating state while transmitting power therebetween.

Another object of the invention is to suggest a contactless connectorand a contactless connector system that transmits power more efficientlyso as to allow for reducing the overall length of the contactlessconnector.

These objects are solved by the subject matter of the independentclaims. Advantageous embodiments are subject to the dependent claims.

The present invention provides a contactless connector for inductivelyconnecting at a mating end a corresponding mating connector as definedin claim 1. Advantageously, a closed magnetic loop is established oncethe contactless connector is coupled to a corresponding matingconnector. The contactless connector comprises an inner ferrite element.This element may also be referred to as center ferrite core, which mayhave a tubular shape, for instance. An inductive coupling element of thecontactless connector is arranged to at least partially surround theinner ferrite element and transmits/receives power to/from thecorresponding mating connector. An outer ferrite element of thecontactless connector is arranged to at least partially surround theinductive coupling element, wherein a front end of the outer ferriteelement facing the mating end is recessed in an axial direction of thecontactless connector with respect to a front end of the inner ferriteelement facing the mating end, and wherein a rear end of the outerferrite element is magnetically connected to a rear end of the innerferrite element. The outer ferrite element may also be referred to asouter ferrite core, which may have a tubular shape.

This specific arrangement of the inner ferrite element and an outerferrite element advantageously may allow an optimized guidance of themagnetic flux and wider flux fields at the head part of the connector,when being inductively coupled to the mating connector. In particular,such that a front end of the outer ferrite core may be recessed withrespect to a front end of the center ferrite core in view of alongitudinal axis (also referred to as axial direction L in thefollowing) of the connector.

For example, such particular arrangement of the recessed outer ferriteelement allows for a satisfactory coupling even under misalignmentsituations between a connector and the counter-connector. Anotheradvantage of the inductive element being, for example, only covered bythe rear portion (the rear portion is defined as being opposite to themating end of the contactless connector) of the outer ferrite core, awide magnetic flux field is provided at the head part of the contactlessconnector. Hence, a reliable transmission/reception of power to/from thecorresponding mating connector may be achieved.

As an example, the inner and outer ferrite elements may mechanically beconnected at their respective rear portions so as to form across-sectional u-shape with an opening facing the mating end of thecontactless connector. Alternatively, the inner ferrite element and theouter ferrite element may, for instance, be integrally provided in asingle piece.

According to another advantage of the specific arrangement of the partsof the contactless connector, this configuration, for example, allowsfor proper power transfer even in case of the coupled connectors areangularly misaligned in view of their longitudinal axes, or in case oflateral/planar mismatch perpendicular to their longitudinal axes.Moreover, the above configuration allows, e.g., for less sensitivitywith regards to a varying distance between two inductively coupledconnectors. This advantageous effect of the connector having lesssensitivity with respect to misalignment may, for instance, be achievedin that a wider flux field is created due to the recessed outer ferriteelement.

Further, due to the specific arrangement, the magnetic field lines maynot, for instance, create a closed magnetic loop inside the samecontactless connector once the mating part is slightly misaligned.Instead, the magnetic field lines may, for instance, still connect tothe ferrite elements of the mating connector due to the wider magneticflux field in a misalignment condition.

The inductive coupling element may as an example only be formed as acoil by using wire, such as for example solid coil wire, multi-strandedcoil wire or the like. The wire material can be any material suitablefor the described purpose, such as for example copper.

As an example, the contactless connector may be employed as acontactless Ethernet coupler with power transmission. In this regard,the contactless Ethernet coupler at the transmitting side may have anexternal power input, and the mating contactless Ethernet coupler at thereceiving side may have an external power output. A part of the externalpower input may be branched off at the transmitting and receiving side,respectively, so as to supply the Ethernet circuits at the transmittingside as well as the Ethernet circuits at the receiving side. This maye.g. allow for flexible applications as well as a large range oftransmittable power. As a variation, at the transmitting side, the powerto be transmitted may, for instance, be inductively obtained from thedata lines at the transmitting side. Optionally, external power supplymay also be applied for maximum flexibility and an increasedtransmittable power level.

As another example, the power to be transmitted by such Ethernet couplermay inductively obtained from the data lines of the transmitting side,whereas the received power may be inductively applied to the data linesat the receiving side. Optional external power input at the transmittingside and optional external power output at the receiving side ispossible. In a variation of this example, the received power at thereceiving side may be used for internal power supply of the receivingside only.

The contactless connector can, for example, also be used in medicalenvironments. In this regard, the connector may be e.g. employed inartificial joints or in human bone structures.

The contactless connector may be, for instance, be provided within aflexible cable, or in a rigid connector case, or an M12 connector case,or a case being thicker and shorter than an M12 connector case, or maye.g. be provided within a square shaped housing, or within an angledcase. Also, the connector may e.g. be provided such that the electroniccircuits of the connector may be provided in a separate case remote fromthe mechanical parts of the connector, whereas a flexible cable connectsboth parts.

As a further example, the contactless connector may be suited for beinge.g. operated in environments containing water and/or oil. In thisregard, the contactless connector is capable of providing a stable andreliable connection to a mating contactless connector, which may also beoperated within watery and/or oily surroundings or be operated outsidethereof. For example, the contactless connector may further be formedsuch that water and/or oil is/are allowed to flow through an inner partof the connector.

The contactless connector of the present invention further comprises aninductive coupling support element arranged around the inner ferriteelement. The inductive coupling support element may also be referred toas mounting support, or mounting bracket for the inductive couplingelement. For example, the inductive coupling support element may bemanufactured of non-conductive/isolating material, such as plastic,resin, or the like. The inductive coupling support element may bearranged around the inner ferrite element such that it contacts at itsinner recess the outer surface of the inner ferrite element, i.e. theinner surface of the inductive coupling support element may contact theouter surface of the inner ferrite element. The recess of the inductivecoupling support element is preferably an opening extending along theentire length of the inductive coupling support element. According to aparticularly preferable embodiment, the inductive coupling supportelement has a hollow cylinder shape having a circular cross-section withan opening extending along the entire longitudinal axis of the inductivecoupling support element.

Advantageously, by means of providing such inductive coupling supportelement, which may e.g. be provided as a bobbin, the mounting of thecoil windings during e.g. an automatic winding process (by a machine,for example) may be significantly simplified. Moreover, the stability ofthe coil windings may be increased with regards to keeping theirposition around the inner ferrite element after the manufacturingprocess. In other words, the coil windings may be firmly held during andafter the winding process. In particular, in case of, for example, thefront part of the connector comprising more coil winding layers than therear part of the connector. Preferably at least one layer of coilwindings is formed on the outer surface of the support element in theform of a first coil winding layer. Further coil winding layers arepreferably formed on top of the first coil winding layer according tothe coil requirements.

The inductive coupling support element of the contactless connector ofthe present invention comprises an intermediate disc with a slot. Theintermediate disc (which may also referred to as intermediate wall)advantageously allows, for instance, dividing and separating thedifferent layers of coil windings of the front and rear parts of thecontactless connector into different coil winding sections, each sectionhaving a preferred number of coil winding layers. The at least oneintermediate disc extends outwardly from the outer surface of theinductive coupling support element. That is, the intermediate discextends in a direction away from the longitudinal axis of the supportelement. According to a preferred embodiment of the support element ithas a hollow cylinder shape and the intermediate disc thus extends alongthe radial direction thereof. The intermediate disc is preferablyarranged between the front and rear end of said inductive couplingsupport element. The intermediate disc has preferably a circularcross-section. The slot advantageously may allow, for example, therouting of the coil windings during an, for instance, automatic windingprocess. Thus, the slot forms a coil wire passageway through which thecoil wire is routed. The intermediate wall can comprise several suchcoil wire passageways, i.e. slots. Furthermore, the slot (which may alsobe referred to a recess of the intermediate disc) may also avoid thatthe manufactured contactless connector has a greater diameter at theregion of the intermediate disc due to the crossed over coil windingsbetween the two sections of the inductive coupling support element,which are divided by the intermediate disc. The slot allows winding ofthe coil wire through the intermediate wall so that preferably one andthe same coil wire forms the various coil winding sections separated bythe at least one intermediate wall.

The inductive coupling element of the contactless connector of thepresent invention is a coil comprising a plurality of windings. Forexample, the windings may be arranged in at least one layer along anouter surface of the support element. Thus, the inductive couplingelement is a wire wound to form a coil comprising a plurality of coilwindings. The coil windings are wound around the inductive couplingsupport element.

According to an advantageous embodiment of the invention which can beused in addition or alternatively to the above the inductive couplingelement is radially, preferably symmetric, arranged around the inductivecoupling support element. For example, the coil windings may be woundaround an outer surface (which faces radially outwards) of inductivecoupling support element. Thus, the coil wire of the coil is woundaround the outer surface of the support element (e.g. bobbin). Accordingto a particularly preferred embodiment the inductive coupling element,i.e. the coil, is formed such that it forms a cylinder shape and thushas a circular cross-section. Since the coil is wound around the supportelement that preferably has a hollow cylinder shape, also the coil'spreferred shape is a hollow cylinder shape.

According to an advantageous embodiment of the invention which can beused in addition or alternatively to the above, the coil comprises morewinding layers in a first section at a front part of the inner ferriteelement that is not surrounded by the outer ferrite element than in asecond section at a rear part of the inner ferrite element that issurrounded by the outer ferrite element.

Advantageously, providing more coil layers at the front section of theinner ferrite element allows for a concentration of windings at thosepart of the inner ferrite element which is not covered by the outerferrite element. Having more layers of coil windings in the frontsection allows for an increased efficiency of power transmission. Hence,the overall length of the contactless connector can be reduced whilemaintaining or even increasing the maximum allowed transfer power levelcompared to a connector with evenly distributed coil layers.

According to another advantageous embodiment of the invention which canbe used in addition or alternatively to the above, the coil comprises aneven number of layers in the first and second sections. This allows for,among others, a cost efficient assembly of such a contactless connector.

According to an advantageous embodiment of the invention which can beused in addition or alternatively to the above, a non-conductive coverelement of the contactless connector is arranged to surround the innerferrite element, the inductive coupling element and at least part of theouter ferrite element. For instance, the non-conductive cover elementmay be a pre-fabricated cover member for mounting the same onto theconnector.

According to a particular preferred embodiment of the invention, thenon-conductive cover element is an overmold. For instance, thenon-conductive cover element may be provided by an overmolding process,such as, for example, an injection molding process. By overmolding theferrite elements and coil windings in order to form such an overmoldcover element, the stability of the entire connector can be improved.

According to another advantageous embodiment of the invention which canbe used in addition or alternatively to the above, the contactlessconnector may comprise a housing element which is spaced from the rearend of the outer ferrite element by a predetermined distance with regardto the axial direction L of the contactless connector.

Advantageously, such configuration of having a gap between the outerferrite element and the housing element allows, for instance,significantly reduces an eddy current, which may occur within thehousing element. The reduction of the eddy current may e.g. reach alevel, where the current loss is negligible. By gap G the distancebetween the back surface of the outer ferrite element and the frontsurface of the housing elements is meant, i.e. the distance measuredalong the longitudinal axis of the connector. It is preferable to setthe distance between the back surface of the outer ferrite element andthe front surface of the housing element between 2 to 3 mm in order toachieve even better results.

According to a further preferred embodiment the contactless connectorcomprises at least one antenna element. The antenna signal can betransmitted at a preferred carrier frequency, such as 60 GHz or 2.4 GHz.The antenna element is preferably arranged within the contactlessconnector and can, for example, be arranged in between the mating end ofthe contactless connector and the front end of the inner ferriteelement. The mating end is, for example, to be understood as a frontside of the inductive coupling support element, wherein the plane of thefront side is perpendicular to the axial direction L of the contactlessconnector. Alternatively, the antenna element can be arranged behind theinner and/or outer ferrite element with respect to the mating end of thecontactless connector. This arrangement behind the inner and/or outerferrite element is, for example, to be understood as that the innerand/or outer ferrite element is in-between the antenna element and themating end of the contactless connector.

The antenna element is for example a loop antenna, a parabolic antenna,dipole antenna, directional antenna, or any other suitable antenna type.In case of a loop antenna type, it is preferred to optimize the same fornear end communication, such that the data transmission is only enabledwithin a short range, e.g. 10 mm or less. Such loop antenna type elementis beneficial since it has reduced cross-talk properties and alsoreduced interference with other electronic devices as well asneighboring other contactless connector pairs.

The antenna is moreover, for example, electrically connected to anelectronic circuit which is arranged in a rear part of the contactlessconnector for transmission and/or for receiving radio waves. Forinstance, the antenna may directly be connected by an antenna connectionline in a right angle. This may further reduce the space requirement ofthe antenna element in the longitudinal direction of the contactlessconnector. In case the antenna element is arranged at the mating end ofthe contactless connector, the connection in a right angle may forexample result in the antenna being arranged close to the inner ferriteelement, thereby, among others, resulting in a compact structure of thecontactless connector.

Advantageously, implementing the antenna element in front of the frontend of the inner ferrite element allows for a short distance to theantenna element of the mating connector. Thus, less transmission poweris required, thereby allowing reducing interference with otherelectronic parts in the vicinity of the connector.

According to an advantageous embodiment of the invention which can beused in addition or alternatively to the above, the contactlessconnector comprises an antenna connection line for connecting theantenna element, wherein the antenna connection line is routed throughthe ferrite element. This preferred embodiment suggests routing theantenna signal or antenna “information” through the ferrite core,preferably through the inner ferrite core. Such a connection line can,for example, be formed by an antenna rod arranged within the innerferrite element opening, in case the at least one antenna element isarranged behind the inner and/or outer ferrite element with respect tothe mating end. This preferred design utilizing the antenna rod hasshown advantageous results for a carrier frequency of approximately 60GHz. In case the antenna element is arranged at the mating end of theconnector, a connection line is preferably routed through the innerferrite core. Both arrangements avoid, for example, the necessity ofproviding the connection line or other connection means e.g. at theradial outer parts of the contactless connector. In case of theconnection line, the necessary length thereof may e.g. be kept to aminimum so that transmission/reception of signals may be improved.

The present invention further provides a contactless connector systemcomprising a contactless connector according to one of the previouslydescribed embodiments and a corresponding mating connector connected tothe contactless connector such that the contactless connector allows fortransmitting/receiving power to/from the corresponding mating connector.

The present invention further provides a method for manufacturing acontactless connector as defined in the independent method claim 11. Theinner ferrite element may be inserted into the recess, preferably intoan opening (e.g. hole) of the inductive coupling support element eitherbefore or after the arrangement of the inductive coupling element aroundthe inductive coupling support element. Preferably the inner ferriteelement is inserted into an opening of an inductive coupling supportelement that has a hollow cylinder shape with a circular cross-sectionwith the opening extending along the entire longitudinal axis of thesupport element.

An advantageous aspect of the method is that it allows for a fullautomatic assembly of the parts mentioned. Hence, a cost efficientmanufacturing of the contactless connector is thereby enabled.

According to a further preferred embodiment of the method, the coilwinding process starts and ends at the same end of the inductivecoupling support element. Preferably the entire coil is formed during acontinuous operation during which one and the same coil wire is wound toform the various coil winding sections that are separated by at leastone intermediate wall. For example, in case of forming a coil on asupport element comprising only one intermediate disc with only oneslot, the coil wire is preferably routed through the same slot twiceduring the process of forming the entire coil, i.e. during formation ofall coil winding sections of the coil. In case of an embodimentcomprising an intermediate wall with two slots, the coil wire ispreferably routed through each slot once during the coil formingprocess.

The accompanying drawings are incorporated into the specification andform a part of the specification to illustrate several embodiments ofthe present invention. These drawings, together with a description,serve to explain the principles of the invention. The drawings aremerely for the purpose of illustrating the preferred and alternativeexamples of how the invention can be made and used, and are not to beconstrued as limiting the invention to only the illustrated anddescribed embodiments. Furthermore, several aspects of the embodimentsmay form—individually or in different combinations—solutions accordingto the present invention. The following described embodiments thus canbe considered either alone or in an arbitrary combination thereof.Further features and advantages will be become apparent from thefollowing more particular description of the various embodiments of theinvention as illustrated in the accompanying drawings, in which likereferences refer to like elements, and wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1a and 1b schematically show a sectional view of a contactlessconnector along a longitudinal axis, a detailed view showing thecross-section of the contactless connector along the line A-A accordingto a first exemplary embodiment of the invention;

FIG. 2 schematically shows a sectional view of the contactless connectorand a corresponding mating connector along a longitudinal axis accordingto the first exemplary embodiment of the invention;

FIG. 3 schematically shows a winding order of the inductive couplingelement of the contactless connector in a sectional view along alongitudinal axis of the contactless connector according to the firstexemplary embodiment of the invention;

FIG. 4 schematically shows a sectional view of the contactless connectoralong a longitudinal axis, according to the first exemplary embodimentof the invention;

FIG. 5 schematically shows a sectional view of a contactless connectorincorporated in a tubular housing, along a longitudinal axis, accordingto the first exemplary embodiment of the invention;

FIG. 6 schematically shows a perspective view of a contactlessconnector, according to a second exemplary embodiment of the invention;

FIG. 7 schematically shows a sectional view of the contactless connectoralong a longitudinal axis, according to the second exemplary embodimentof the invention;

FIG. 8 schematically shows a perspective view of the inductive couplingelement and inductive coupling support element of the contactlessconnector according to the second exemplary embodiment of the invention;

FIG. 9 schematically shows a further perspective view of the inductivecoupling element and inductive coupling support element of thecontactless connector according to the second exemplary embodiment ofthe invention;

FIG. 10 schematically shows a winding order of the inductive couplingelement of the contactless connector in a sectional view along alongitudinal axis of the contactless connector according to the secondexemplary embodiment of the invention;

FIG. 11 schematically shows a perspective view of the ferrite elementsof a contactless connector according to the second exemplary embodimentof the invention; and

FIG. 12 schematically shows a sectional view of the contactlessconnector including another antenna configuration along a longitudinalaxis, according to the first exemplary embodiment of the invention.

DETAILED DESCRIPTION

FIGS. 1 to 5 and 12 show a first preferred embodiment of the contactlessconnector, whereas FIGS. 6 to 11 show a second preferred embodiment of acontactless connector. Similar parts, elements and/or structures in bothembodiments may be denoted by the same reference signs in the followingdescription.

Referring to FIG. 1a , a sectional view of a contactless connector 100along a longitudinal axis is illustrated. Furthermore, FIG. 1billustrates a cross-section of the contactless connector 100 of FIG. 1aalong the line A-A.

In the following, the term contactless connector is used. It should benoted that a contactless connector may also be a contactless plugconnector.

According to the sectional view of the contactless connector 100 of FIG.1a , the illustration shows the front end assembly of the contactlessconnector 100. The front end assembly is symmetrical with respect to theaxis (longitudinal axis) as shown by the horizontal dotted line of FIG.1a . In other words, the contactless connector 100 is circularlyarranged around the axis. The circular arrangement of the connector canespecially be derived from the cross sectional view of FIG. 1 b.

As further shown in FIG. 1a , the contactless connector 100 comprises aninner ferrite element 102 which has preferably a tubular shape so thatthe inner ferrite element 102 is closely arranged around the centeraxis, i.e. The longitudinal axis as shown by the horizontal dotted line.Due to the tubular shape, the inner ferrite element 102 comprises acylindrical opening along the longitudinal axis. This is also referredto as hollow opening 106 of the inner ferrite element 102 in thefollowing.

Moreover, the contactless connector 100 comprises an outer ferriteelement 107 that is also symmetrically arranged around the longitudinalaxis. The outer ferrite element 107 is also tubular shaped with adiameter that is larger than that of the inner ferrite element 102. Suchdifference in diameters results in a space between the outer surface ofthe inner ferrite element 102 and the inner surface of the outer ferriteelement 107.

As can further be seen from FIG. 1a , the length of the outer ferriteelement 107 in view of the longitudinal direction L (parallel to thelongitudinal axis) is shorter than the length of the inner ferriteelement 102 along the longitudinal axis. In other words, a front end 108of the outer ferrite element 107 is recessed with respect to a front end103 of the inner ferrite element 102. Thereby, the expression “frontend” denotes the tip of the contactless connector 100 that faces amating end 101 of the connector 100. The mating end 101 is defined asthat end of the contactless connector 100 that faces a counter-partconnector, i.e. a mating connector 200 (mating contactless connector200). Thereby, the counter-part contactless connector 200 is that partwhich receives power transmitted by the contactless connector 100 asshown in FIG. 1 a.

Further, according to the embodiment, the specific arrangement of thefront end 108 of the outer ferrite element 107 being recessed withrespect to the front end 103 of the inner ferrite element 102 results inthe effect of having an improved coupling behavior between thecontactless connector 100 and the corresponding mating connector 200.That is, recessing the outer ferrite tube element 107 leads to lesssensitivity to misalignment of the contactless connector 100 and thecorresponding mating connector 200. This will be further described inconnection with FIG. 2.

In addition, FIG. 1a shows that the rear end 109 of the outer ferriteelement 107 and the rear end 104 of the inner ferrite element 102 aremagnetically connected. This may for instance be a magnetic connectionbetween the outer and inner ferrite elements having an air gap inbetween. According to an exemplary realization of this embodiment, theouter and inner ferrite elements 107, 102 may be integrally provided inone single piece, as shown in FIG. 1a . However, in a further exemplaryrealization of this embodiment, the outer and inner ferrite element,respectively, may also be comprised of a plurality of ferrite (block)elements which do not comprise an air gap between the elements and aremechanically contacted to each other. This contact may for instance bean adhesive contact or soldered, glued or bonded by various means.According to another exemplary realization of this embodiment, the outerand inner ferrite element, respectively, may be comprised of a pluralityof ferrite pieces (ferrite block elements) with one or more air gaps inbetween. According to another exemplary realization of this embodiment,either the outer ferrite element 107 or the inner ferrite element 102 isintegrally provided in one single piece (that is, fabricated in onepiece), whereas the respective other one is comprised of a plurality offerrite blocks/pieces.

According to the embodiment relating to FIG. 1a , the inner ferriteelement 102 and the outer ferrite element 107, which are connected attheir respective rear portions, form a cross-sectional U-shape having anopening at the front end of the contactless connector 100 with respectto a sectional view along the longitudinal axis as illustrated in FIG. 1a.

As to the inner ferrite element 102, same may be a tubular shapedelement, which is the core ferrite element, that has in an exemplaryembodiment an outer diameter of 4 millimeters+/−0.1 millimeter and aninner diameter of 2 millimeters+/−0.3 millimeters and a length of 12millimeters+/−0.6 millimeters.

The outer ferrite element 107, which may also have a tubular shape, hasin an exemplary embodiment a length of 6 millimeters+/−0.15 millimeters,an outer diameter of 9 millimeters+/−0.4 millimeters and an innerdiameter of 7 millimeters+/−0.3 millimeters.

Furthermore, the inner and outer ferrite elements may be providedintegrally in a single piece according to an exemplary realization ofthe embodiment.

According to another exemplary realization of the embodiment, the innerferrite element 102 may further comprise a socket disc (which denotesthe rear part of the inner ferrite element 102 or, in other words, therear part of the entire ferrite core assembly), wherein this socket discmay have a thickness of 2 millimeters+/−0.3 millimeters on which the,for instance, tubular shaped outer ferrite element 107 is mountedthereon in the axial direction L.

In accordance with the above described exemplary realization, includingthe above-mentioned dimensions of the inner and outer ferrite elements,there may be two layers of coil windings 115 around the inner ferriteelement 102 beginning at the rear end of the U-shaped opening (withrespect to the sectional view of FIG. 1 a) of both ferrite elements ofthe contactless connector 100. As further exemplarily shown in FIG. 1a ,there may be three layers of coils windings 115 around the inner ferriteelement 102 in an area where the coils windings 115 are not surroundedby the outer ferrite element 107 in the longitudinal direction L.

In a further exemplary implementation of the embodiment, the contactlessconnector 100 comprises a housing element 111 (as further illustrated inFIG. 1a ), which may be, for instance, located outside the outer ferriteelement 107. That is, the housing element 111 may contact, according tothis first exemplary implementation of the embodiment, the outer surfaceof the outer ferrite element 107. Hence, the diameter of the housingelement 111 is larger than the diameter of the outer ferrite element107. The housing element 111 may be employed so as to provide asufficient level of heat dissipation and/or additional stability of theconnector arrangement. According to an exemplary realization of theembodiment, the housing element 111 may, for instance, be of metal. Ifselecting metal as the material, the housing element 111 may also act asa shielding element for circuitry provided inside the connector.

Moreover, it should be noted that the specific area of the housing 111that directly contacts the outer surface of the outer ferrite element107 is directional proportional to the standing loss i.e. eddy currentcaused. Hence, reducing this contact area, which is achieved byrecessing the front end 112 of the housing 111 with respect to the frontend 108 of the outer ferrite element 107 (and thus also with respect tothe front end 103 of the inner ferrite element 102), results in areduction of the eddy current. Thereby, the efficiency of the powertransmission of the connector can significantly be increased.

According to a further exemplary realization of the embodiment, thehousing element 111 of the contactless connector 100 may be provided ofcopper, aluminum, nickel, tin or an alloy thereof such as brass (55-86%copper). Also, the housing 111 may be nickel plated.

According to another exemplary realization of the embodiment, thehousing element 111 may, for instance, be of plastic. Such realizationwould reduce the manufacturing costs while providing satisfactorymechanical stability of the connector.

According to this first embodiment, the housing element 111 as shown inFIG. 1a is recessed with respect to the outer ferrite element 107. Inmore detail, the front end of the housing is recessed in the axialdirection L of the connector 100 with respect to the front end 108 ofthe outer ferrite element 107.

In the above description, the expression “recessed” has been used so asto demonstrate the different lengths/positions of the inner ferriteelement 102, the outer ferrite element 107 and the housing element 111along the longitudinal axis. However, these specific relations may alsobe described in that the outer ferrite element 107 protrudes from thehousing element 111 by a specific length in the axial direction L.Further, with respect to the dimensions in the axial directions of theferrite elements, FIG. 1a shows that the inner ferrite element 102protrudes from the outer ferrite element 107 towards the mating end 101of the contactless connector 100 in the axial direction L.

According to the embodiment that relates to FIG. 1a , the contactlessconnector 100 further comprises an inductive coupling element 110 whichsurrounds the inner ferrite element 102. This inductive coupling element110 is used for transmitting or receiving power to or from acorresponding mating connector 200. Although not shown in FIG. 1a , thisinductive coupling element 110 may receive electrical power from asupply line of an electronic circuit 401 (also not shown) so thatcurrent flows through the inductive coupling element 110. In combinationwith the ferrite elements, the inductive coupling element 110establishes an electromagnetic field which then is received by aninductive coupling element of the corresponding mating connector 200.

In an exemplary realization of this embodiment, the inductive couplingelement 110 may be at least one coil layer. Alternatively, the inductivecoupling element 110 according to another exemplary realization of thisembodiment may be comprised of coil windings (the material may, forinstance, be copper) which are provided around the inner ferrite element102 and partially covered by the outer ferrite element 107. Asillustrated in FIG. 1a , different amount of layers (at least one layer)of such coil windings 115 may be used for the inductive coupling element110. Although FIG. 1a shows coil windings, this merely exemplarily showsone implementation of the inductive coupling element 110 of theembodiment. The inductive coupling element 110 may also comprise atleast one foil layer, such as e.g. a copper foil layer, instead of thecoil windings 115 illustrated in FIG. 1 a.

According to the embodiment that relates to FIG. 1a , the inductivecoupling element 110 may only be partially covered/surrounded by theouter ferrite element 107. That is, the inductive coupling element 110may be surrounded by the outer ferrite element 107 in a rearportion/rear end of the inner ferrite element 102, whereas the inductivecoupling element 110 is not surrounded/not covered by the outer ferriteelement 107 in a front part of the inner ferrite element 102, whereinthe front part/front end is defined as that part which faces the matingend 101 of the contactless connector 100.

Furthermore, according to another exemplary realization of thisembodiment, the coil comprises more winding layers in a first section(which is located at the front part/end 103 of the inner ferrite element102) than in a second section (which is located at the rear part of theinner ferrite element 102). This specific arrangement of coil windingscan be seen in FIG. 1a . For instance, the inner ferrite element 102 maybe surrounded by two coil winding layers with respect to the entirelength of the inner ferrite element 102 in the axial direction L,whereas the front part of the inner ferrite element 102 may besurrounded by three layers of coil windings. It should be noted that theamount of coil winding layers at the front part/end is not limited tothree layers, but is preferably more than the number of coil windinglayers that surround the rear part of the inner ferrite element 102.

Moreover, the specific arrangement of providing more winding layers atthe front portion of the inductive coupling element 110, as described inthe exemplary realization of this embodiment, allows for an increase ofefficiency which also results in the advantage and technical effect ofincreasing the transmittable power per volume ratio at the contactlessconnector 100. As the efficiency of the power transmission is improvedby the above specific arrangement, a significant reduction of theoverall length of the front end assembly of the contactless connector100 is achieved. For example, the above described contactless connector100 may have a front end diameter of 10.5 millimeters, a front endassembly length of 12 millimeters and be capable of transferring powerat a 10-15 Watt level with high efficiency.

In a further exemplary realization of the embodiment, the contactlessconnector 100 may additional comprise a non-conductive cover element114, which may be provided of resin, plastic or the like, wherein thenon-conductive cover element 114 is arranged to surround the innerferrite element 102, the inductive coupling element 110 and at leastparts of the outer ferrite element 107. The non-conductive cover element114 may also entirely cover the outer ferrite element 107 in case nohousing element 111 is provided at the contactless connector 100.

According to a further exemplary realization of the embodiment, in caseof a housing element 111 being provided at the contactless connector100, the non-conductive cover element 114 may substantially cover thatfront part of the outer ferrite element 107 which is not covered by thehousing, as well as that part of the inductive coupling element 110which is not covered by the outer ferrite element 107, as well as thefront surface (which is perpendicular to the axial direction) of themating end 101 of the contactless connector 100. Further, as shown inFIG. 1a , the non-conductive cover element 114 covers theabove-described parts of the contactless connector 100 so that theresulting contactless connector 100 has a cylindrical shape with thediameter of the housing element 111, whereas the front portion of thenon-conductive cover element 114 extends beyond the front end 103 of theinner ferrite element 102 by a certain amount with respect to thelongitudinal axis direction L.

According to another exemplary realization of the embodiment, wherein,in case the contactless connector 100 comprises a housing element 111,at least a part of the non-conductive cover element 114 is overlapped bythe housing element 111.

According to an exemplary realization of the embodiment, the distancebetween the front end 112 of the housing 111 and the front end 108 ofthe outer ferrite element 107 may, for instance, be 4 millimetersapproximately. Further, the distance between the front end 103 of theinner ferrite element 102 and the front end 108 of the outer ferriteelement 107 may be 5 millimeters approximately. Following from that, thedistance between the front end 112 of the housing 111 and the front end103 of the inner ferrite element 102 may, for instance, be 9 millimetersapproximately. Moreover, the overall length of the front end assembly,which denotes the overall length in the axial direction L measured fromthe front end 103 of the inner ferrite element 102 to the rear end 113of the ferrite elements may, for instance, be approximately 12millimeters.

Overall, as described in the various exemplary implementations of theembodiment, the advantages of increasing the efficiency of powertransmission as well as of reducing the sensitivity to misalignment ofthe connector 100 in the mating state is achieved by at least arrangingthe inner ferrite element 102 such that same protrudes from the outerferrite element 102. In other words, these advantages are achieved byrecessing the front end 108 of the outer ferrite element 107 withrespect to the front end 103 of the inner ferrite element 102.

Further increase of the efficiency of power transmission, which allows areduction of overall length of the connector, is achieved byadditionally providing more coil windings in the front portion of thecontactless connector 100.

Additionally implementing a (metal) housing element 111 which isrecessed with respect to the outer ferrite element 107 has the effect ofreducing loss of current, such as eddy current, significantly as thearea of those parts of the housing 111 which directly surround orcontact the outer ferrite element 107 is reduced. In other words, thearea/surface of the housing 111 in which the magnetic field may causeeddy current/heat, is reduced.

It is noted that in this exemplary first embodiment, it is describedthat the housing element 111 overlaps a part of the outer surface of theouter ferrite element 107. However, the housing element 111 may also befurther recessed with respect to the rear end 109 of the outer ferriteelement 107 so as to not have an overlap i.e. to not have a directcontact between the housing element 111 and the outer ferrite element107. This is subject to the second exemplary embodiment according toFIGS. 6 to 11 which are described below.

As mentioned above, FIG. 1b illustrates a cross-section of thecontactless connector 100 of FIG. 1a along the line A-A.

As can be seen from FIG. 1b , the non-conductive cover element 114 hasbeen omitted so as to illustrate the housing element 111, the inner andouter ferrite elements 102, 107 and the inductive coupling element 110as already described in detail in connection with FIG. 1a . AlthoughFIG. 1b shows parts of the outer ferrite element 107, this onlyexemplarily demonstrates that the inductive coupling element 110, whichis exemplarily shown in FIG. 1b as coil windings 115, have a smallerouter diameter than the outer diameter of the tubular shaped outerferrite element 107. However, it is noted that according to anotherexemplarily realization of the embodiment, the outer diameter of theinductive coupling element 110 of the contactless connector 100 may beequal to the diameter of the outer ferrite element 107.

FIG. 2 shows a sectional view, along a longitudinal axis, of thecontactless connector 100 and a corresponding mating connector 200 in amating state, according to an embodiment of the invention. Suchconfiguration is also referred to as contactless connector systemaccording to the invention.

As can be seen from the figure, a contactless connector 100 and a matingconnector 200 are arranged oppositely to each other and aligned alongthe longitudinal axis (horizontal dotted line). That is, the respectivemating ends 101/201 of the connectors face each other while having anair gap 217 between the mating ends 101/201. As an example, the air gap217 may be approximately 5 millimeters. As indicated by the magneticfield lines 216, in the mating state of the connectors, a closedmagnetic loop is established. Due to the recessed outer ferrite elements107/207 of both illustrated connectors, it is achieved that the fieldlines 216 tend to keep magnetically connecting the outer ferriteelements 107/207 of both contactless connectors 100/200, even in case ofthe connectors being planar misaligned in the direction perpendicular tothe longitudinal axis. Also, the magnetic field lines 216 flowing in theinner ferrite elements 102/202 of both connectors are prevented fromcreating a closed magnetic loop inside the respective same contactlessconnector in case of such planar misalignment between the twoconnectors. In more detail, the magnetic field lines 216 are preventedfrom flowing back from the outer ferrite element 107 into the innerferrite element 102 within contactless connector 100, (and the same forthe mating connector), in case of such planar misalignment between thetwo connectors.

Hence, it is apparent that the illustrated configuration allows forproper power transfer not only in case of lateral/planar mismatchperpendicular to their longitudinal axes, but also even in case of thecoupled connectors being angularly misaligned in view of theirlongitudinal axes. According to the above described implementations ofthe embodiment, the configuration thus also allows for less sensitivitywith regards to varying distance (air gap) between two inductivelycoupled connectors.

The effect of having less sensitivity in an misalignment condition ofthe inductively connected connectors can basically seen as a result fromthe establishment of a wider flux field due to the recessed outerferrite elements 107/207 compared to a case where the outer ferriteelements would not be recessed.

FIG. 3 shows a winding order of the inductive coupling element 110 ofthe contactless connector 100 in a sectional view along a longitudinalaxis of the contactless connector, according to further exemplaryembodiment of the invention.

Each rectangle in FIG. 3 comprising a number schematically representsthe cross-section of a coil winding 115 (which actually would have acircular shape).

As to the winding order description, the winding starts and ends at theinner rear portion (inner side that is opposite to the mating end 101 ofthe connector 100) of the U-shaped inner and outer ferrite elements(this inner rear portion may also be referred to as side of the ferritecore base (disc) of the ferrite elements that is opposite to the matingend 101 of the connector 100).

-   -   In a first step, the first and inner most layer starts from the        ferrite core base (disc), wherein a coil 115 is wound around the        inner ferrite element 102 into the direction of the mating end        101 front end of the inner ferrite element 102.    -   In a second step, a second layer of coil windings is created by        winding the coil 115 at the tip of the inner ferrite element 102        followed by a third layer at the tip of the inner ferrite        element 102.    -   Subsequently, the second step is repeatedly performed (coil        windings are alternately arranged in the two different layers)        in the direction to the inner rear portion of the ferrite        elements until reaching the front end 108 of the outer ferrite        element 107. This may, for instance, result in a 6×3 layer of        coil windings 115.    -   After that, in the next step, it is continued with winding the        coil 115 only in the second layer until reaching the ferrite        core base (disc), which is the inner rear portion of the ferrite        elements.

FIG. 4 schematically shows a sectional view of the contactless connector100 along a longitudinal axis, according to a further exemplaryembodiment of the invention.

FIG. 4 shows an antenna configuration including an antenna element 402located in the front portion of the connector 100. The antenna element402 is of loop antenna type.

The antenna element may, e.g., be mounted between the mating end 101 ofthe contactless connector 100 and the front end 103 of the inner ferriteelement 102. For example, the antenna element 402 may be implemented(molded within) in the non-conductive cover element 114 at the front endof the contactless connector 100. Such antenna element 402 allows for awireless data transfer independent from the power transmission betweentwo mated connectors. The antenna may, for example, provide high datarate transfer up to a distance of 5 millimeters in the longitudinaldirection towards the mating connector. In another exemplaryrealization, the antenna may be implemented as an RF near field antennacoupling element.

According to an exemplary implementation of the embodiment, theconnection line of the antenna element 402 may be fed through the hollowinner portion 106 of the inner ferrite element 102 so as to beelectrically connected to an electronic circuit 401 (being located in arear part of the contactless connector 100) for transmission and/or forreceiving radio waves. The hollow center of the ferrite core (innerferrite element 102) thus provides a path for an impedance controlledtransmission line towards the antenna element 402 at the front of thecontactless connector 100.

Advantageously, implementing the antenna element 402 in front of thefront end 103 of the inner ferrite element 102 allows for a shortdistance to another antenna element 402 of the corresponding matingconnector 200. Thus, less transmission power is required, therebyreducing interference with other electronic parts in the vicinity of themated connectors.

According to a further exemplary implementation of the embodiment, avacuum assisted potting 405 may be provided behind the rear end of theferrite elements of the contactless connector 100 so as to allowcompletely filling the front end assembly of the contactless connector100 and to provide stability and solid integration of the assemblywithin the tube housing of the entire connector (see also FIG. 5).

FIG. 4 shows the coil power supply line 404 between the ferrite elementsand the electronic circuit 401. The coil power supply line 404 suppliescurrent to the coil windings 115 of the inductive coupling element 110.

The connector case 501 as shown in FIG. 5, may for instance be of amaterial with high electrical conductivity (for low eddy current loss)and thermal conductivity (for good heat spread), in particular at thearea of the case 501 which is near the inner and outer ferrite elements102, 107.

According to a further exemplary implementation of the embodiment, athread 403 may be provided on the outer surface of the housing 111. Forinstance, if implementing the connector as an M12 connector, an M12connector thread may be provided.

FIG. 5 schematically shows a sectional view of a contactless connector100 incorporated in a tubular connector case 501, along a longitudinalaxis, according to another exemplary embodiment of the invention.

The entire connector arrangement provided in the tubular connector case501 may comprise, for example, the contactless connector 100, as shownin FIGS. 1 to 4, being incorporated at the front/head section of theillustrated connector case 501, the electronic circuit 401 surrounded bythe tubular connector case 501, a thread 403 at the outer surface of thetubular connector case 501, and a connection interface 502 at the rearend of the tubular connector case 501, allowing connection to furthercircuitry (not shown). According to a further exemplary implementationof the embodiment, the tubular connector case 501 may be implemented asa contactless M12 connector. In such case, the tubular connector case501 has a small M12 form factor, whereas the thread 403 at the outersurface of the tubular connector case 501 may be an M12 connectorthread.

In one exemplary implementation, the outer diameter of the M12 connectorshown in FIG. 5 may approximately be 10.5 millimeters at the front end(head part of the connector). Further, the outer diameter of the tubularconnector case 501 of the M12 connector shown in FIG. 5 mayapproximately be 12.5 millimeters, whereas the inner diameter of thetubular connector case 501 of the M12 connector shown in FIG. 5 mayapproximately be 9.6 millimeters.

Following FIGS. 6 to 11 show a second preferred embodiment of theinvention. Features of this second embodiment that are similar to thoseof the first embodiment will not be repeated in the following. Hence,same reference signs used in the first and second embodiment describedsimilar parts.

FIG. 6 schematically shows a perspective view of some parts of acontactless connector 100, in particular an inductive coupling supportelement 601 according to this second embodiment.

As can be seen in this figure, the inductive coupling support element601 is circularly arranged around the inner ferrite element 102.Therefore, the inductive coupling support element 601 comprises acylindrical recess or opening (e.g. hole) along its longitudinal axis(which is the axial direction L of the contactless connector 100) so asto allow accommodating of the inner ferrite element 102 in the recess oropening.

Further, as can be seen from FIG. 6, the inductive coupling supportelement 601 comprises a front disc 604 which is arranged such that theplane of the front disc 604 is perpendicular to the axial direction L ofthe contactless connector 100. The front disc 604 is provided at themating end 101 side of the contactless connector 100.

Moreover, as shown in FIG. 6, the inductive coupling support element 601comprises an intermediate disc 602 which is arranged such that the planeof the intermediate disc 602 is also perpendicular to the axialdirection L of the contactless connector 100.

However, the intermediate disc 602 is displaced from the front disc 604towards the rear end of the contactless connector 100 along the axialdirection L of the contactless connector 100, thereby forming a spacebetween the front and intermediate discs 604, 602. The space formed bysaid discs 602, 604 provides an area in which coil windings can bearranged. In particular, the provision of front and intermediate discs604, 602 facilitates the mounting of coil windings 115 by an automaticmounting process. Furthermore, such discs 602, 604 allow to firmly keepthe mounted coil windings 115 in their respective positions aftermanufacturing.

In order to allow a connection of the coil windings 115 to and from thearea between the front disc 604 and the intermediate disc 602, a slot603 is provided at the intermediate disc 602. The slot 603 may be asmall notch or groove with respect to the outline of the intermediatedisc 602, or may reach to that surface of the inductive coupling supportelement 601 which surrounds the inner ferrite element 102. Further, theslot 603 may have various widths. For instance, the width may allowaccommodating at least two coil windings 115 in juxtaposition.

It should be noted that the inductive coupling support element 601 may,for instance, be referred to as bobbin.

The inductive coupling support element 601 according to FIGS. 6 to 11and as described in the following in connection with the secondembodiment may also be implemented to the contactless connector 100 asshown in FIGS. 1 to 5 and 12 as described above in connection with thefirst embodiment.

FIG. 7 schematically shows a sectional view of a contactless connector100 having incorporated an inductive coupling support element 601 asdescribed with regard to FIG. 6 and mounted coil windings 115.

As can be seen in this figure, the inductive coupling support element601 further comprises a rear disc 702 which is arranged such that theplane of the rear disc 702 is also perpendicular to the axial directionL of the contactless connector 100. The rear disc 702 is displaced fromthe intermediate disc 602 towards the rear end of the contactlessconnector 100 along the axial direction of the contactless connector 100thereby forming a space for accommodating coil windings between saidrear disc 702 and said intermediate disc 602. For instance, the reardisc 702 may contact the inner rear portion of the outer ferrite element107 (termed ferrite core base (disc) in the previous embodiment) as bestseen in FIG. 7.

The outer diameters of the front disc 604 and intermediate disc 602 areequal, whereas the outer diameter of the rear disc 702 is less than thatof the front and intermediate discs in the embodiment shown in FIG. 7.For example, the respective outer diameter of the discs may be relatedto the outer diameter of the inductive coupling element 110, i.e. Theheight of the coil windings layers in respective front and rear sectionsof the inductive coupling support element 601.

FIG. 7 further exemplarily shows that the front section (i.e. the spacebetween the front disc 604 and the intermediate disc 602) of theinductive coupling support element 601 comprises 4 layers of coilwindings 115, whereas the rear section (i.e. the space between theintermediate disc 602 and the rear disc 702) of the inductive couplingsupport element 601 comprises 2 layers of coil windings 115. Accordingto a further implementation of this embodiment, both sections, the frontand rear sections, of the inductive coupling support element 601comprise an even number of layers of coil windings 115.

The contactless connector 100 includes an antenna configurationincluding antenna element 402 a provided at the mating end 101 of thecontactless connector 100 has only one bend at its connection point.That is, the antenna element 402 a may, for instance, be contacted bythe antenna connection line 701, whereas the antenna connection line 701contacts the antenna element 402 a by a right angle. In this example ofthe embodiment, there is no need for a (seen in a sectional view)U-shaped antenna element 402 as for instance shown in the embodiment ofFIG. 4. Consequently, the antenna element 402 a according to thisembodiment allows for being mounted directly at the surface of the frontdisc 604 of the inductive coupling support element 601, therebyproviding an even more overall compact structure, in particular in theaxial direction L. Furthermore, the antenna connection line 701 may befed through the inner ferrite element 102. The antenna element 402 a isconfigured to preferably operate at a 2.4 GHz frequency range.

As can further be seen in FIG. 7, the front end 112 of the housingelement 111 a is recessed with respect to the rear end 113 of theferrite elements of the contactless connector 100. The distance/gap Gtherebetween is preferably between 2-3 millimeters, at which tests haveshown that the eddy current loss is negligible.

FIG. 7 further illustrates that a non-conductive cover element 114 a isprovided around the connector arrangement so as to also fill the gap Gbetween the rear end 113 of the ferrite elements and the housing element111 a. In the shown preferred embodiment, the non-conductive coverelement is an overmolded part 114 a and ensures that the entireconnector has a sufficient level of mechanical robustness/stability.Hence, according to this exemplary implementation of the embodiment,there is no need for an overlap between the housing element 111 a andthe outer surface of outer ferrite element 107 in order to providemechanical stability of the connector arrangement. This is not onlybeneficial from a manufacturing point of view, but also provides a morecompact connector design in the radial direction. That is, this aspectof this preferred embodiment enables a more compact design due to lackof overlapping sections between the housing element 111 a and the outerferrite element 107.

FIG. 8 schematically shows a perspective view of the inductive couplingsupport element 601, i.e. bobbin, and the coil windings 115 a accordingto FIG. 7, being attached to an electronic circuit 401.

As the front section of the inductive coupling support element 601 maysupport more winding layers than the rear section of the inductivecoupling support element 601, the coil windings intersect in the area ofthe slot 603 during the automated winding process of the coil windings115 a.

The inductive coupling support element 601, i.e. the bobbin, furthercomprises two mounting pins 801 which protrude of the rear disc 702parallel to the axial direction L of the contactless connector 100.These mounting pins 801 hold metallic pins 802 a, 802 b, respectively asbest seen in FIG. 8. The metallic pins 802 a, 802 b are connected to theelectronic circuit 401. Thus, the metallic pins 802 a, 802 b fulfill asimilar function as the coil power supply line 404 as shown in FIG. 4.Hence, the metallic pins 802 a, 802 b are the supply lines to the coilaccording to this embodiment.

The mounting pins 801 of the inductive coupling support element 601,i.e. bobbin 601, protrude through the back surface 113 of the outerferrite element 107, in particular through the openings 1101 of theouter ferrite element 107 as best seen in FIG. 11. The wire forming thecoil is wound around the metallic pins 802 a, 802 b and fixed thereto.The wire of the coil windings 115 a will then be held by the mountingpin 801 as seen in FIG. 8, which has a recess portion adapted to thewire shape. The electrical current flows therefore from the PCB, to themetallic pins 802 a, 802 b and then through the wire of the coilwindings 115 a for transmitting/receiving power to/from thecorresponding mating connector. Accordingly, the flow of current knownto the skilled person is thereby ensured. FIG. 9 illustrates how theantenna element 402 a is arranged at the front disc 604 of the inductivecoupling support element 601. In this example, the antenna element 402 ais circularly arranged along the outside shape of front disc 604 of thebobbin 601.

FIG. 10 shows a winding order of the inductive coupling element 110 ofthe contactless connector 100 in a sectional view along a longitudinalaxis of the contactless connector, according to further exemplaryembodiment of the invention.

Each rectangle in FIG. 10 comprising a number schematically representsthe cross-section of a coil winding 115 (which actually would have acircular shape).

Furthermore, the shaded parts of the sectional illustration in FIG. 10denote the inductive coupling support element 601 including the frontdisc 604, intermediate disc 602 and rear disc 702 thereof.

As to the winding order description, the winding starts and ends at therear disc 702. In particular, before starting the winding process aroundthe bobbin 601, the coil wire is wound around the first metallic pin 802a and then introduced into the bobbin 601. After completion of variouslayers of coil winding 115 a around the bobbin 601—to be described inmore detail below—the process is finished by winding the coil wirearound the second metallic pin 802 b.

This winding process is also illustrated in FIG. 9, which shows that onewire end of the coil wire exiting the bobbin 601—at the rear disc 702area—is exiting from the uppermost wire layer. Further, FIG. 8 detailsthat another wire end of the coil wire entering the bobbin 601 areaenters after being wound around metallic pin 802 a, and the wire isarranged in the lower layers once the coil is formed and supported bythe bobbin 601. In the following the automated coil winding process willbe described in further detail:

-   -   In a first step, the first and inner most layer starts from the        rear disc 702, wherein a coil 115 is wound around the bobbin 601        into the direction of the front disc 604. According to this        example of the embodiment, the coil is routed through the slot        603 of the intermediate disc 602 of the bobbin 601 between the        6^(th) and 7^(th) windings.    -   In a second step, a second layer of coil windings of the front        section of the inductive coupling support element 601, i.e. the        bobbin 601, is created by winding the coil 115 from front disc        604 until reaching the intermediate disc 602. Then, the next        winding (illustrated by winding 17 in FIG. 10) is provided in a        third layer.    -   In a third step, the third layer is continued until again        reaching the front disc 604 (illustrated by winding 21 in FIG.        10). Then, the next winding (illustrated by winding 22 in        FIG. 10) is provided in a fourth layer.    -   In a fourth step, the fourth layer of the front section of the        inductive coupling support element 601 is continued until again        reaching the intermediate disc 602. Upon routing the wire of the        coil through the slot 603, windings are continued at a second        layer of the rear section of the inductive coupling support        element 601 in the direction to the inner rear portion of the        ferrite elements until reaching the rear disc 702 of the bobbin        601.

According to this example, the front section of the inductive couplingsupport element 601 may comprise 4 layers of coil windings 115, whereasthe rear section of the inductive coupling support element 601 maycomprise 2 layers of coil windings 115. FIG. 10 relates to an exampleonly and shows that even number of layers of coil windings are obtainedin the front and rear sections of the inductive coupling support element601 by utilizing an automated winding process.

The inner ferrite element 102 may be introduced into the bobbin 601,before, during or after the above described winding process, dependingon the preferred manufacturing settings. The bobbin 601 with completedwindings is than arranged in the outer ferrite element 107, whereas itis possible to also arrange the inner ferrite element 102 inside thebobbin 601 first after said bobbin 601 with coil windings has beenarranged within the outer ferrite element 102. Hence, FIG. 10 shows theassembled stage of the bobbin 601, inner and outer ferrite elements 102,107.

The front disc 604 can be removed after the coil winding process (notshown). Thus, the bobbin finally mounted into the connector does notnecessarily comprise a front disc.

FIG. 11 schematically shows a perspective view of the ferrite elementsof the contactless connector 100, according to another exemplaryembodiment of the invention.

According to the illustration in this figure, the rear end 113 (which isthe bottom) of the outer ferrite element 107 comprises openings 1101 soas to accommodate the mounting pins 801 of the inductive couplingsupport element 601.

Feeding the power supply lines, i.e. the metallic pins 802 a, 802 bthrough the inside of mounting pins 801 further allows for thecontactless connector to comply with the M12 form factor. In particular,as the metallic pins then do not have to be routed at the outer surfaceof the outer ferrite element 107.

FIG. 12 schematically shows a sectional view, along a longitudinal axisL, of the contactless connector 300 including another antennaconfiguration. The contactless connector 300 is based on respectivecontactless connectors 100, 200 as shown in FIGS. 1-5 wherecorresponding parts are given corresponding reference numerals andterms. The detailed description of corresponding parts has been omittedfor reasons of conciseness.

Specifically, the contactless connector includes an inner ferriteelement 102; an inductive coupling element 110 arranged to at leastpartially surround the inner ferrite element 102; and an outer ferriteelement 107 arranged to at least partially surround the inductivecoupling element 110. The front end 108 of the outer ferrite element 107facing the mating end is recessed in an axial direction with respect toa front end 103 of the inner ferrite element 102. The rear end 109 ofthe outer ferrite element 107 is magnetically connected to the rear end104 of the inner ferrite element 102.

As shown in the various illustrations of the first embodiment, the innerferrite element 102 has preferably a tubular shape so that the innerferrite element 102 may be closely arranged around the centre axis, i.e.the longitudinal axis L as shown by the horizontal dash-dotted line. Dueto the tubular shape, the inner ferrite element 102 comprises acylindrical opening along the longitudinal axis. This opening is alsoreferred to as hollow opening 106 of the inner ferrite element 102 inthe following. The contactless connector 300 additionally includes anantenna configuration including an antenna element 402 b that isarranged behind the inner and/or outer ferrite element 102, 107 withrespect to the mating end of the contactless connector 300. In otherwords, the arrangement of the antenna element 402 b is positioned withinthe contactless connector 300, namely where the inner and/or outerferrite element 102, 107 is in-between the antenna element 402 b and themating end 103 of the contactless connector 300. For example, theantenna element 402 b may be realized having a dipole structure. Theantenna element 402 b is configured to preferably operate at a 60 GHzfrequency range.

Such an arrangement of the antenna element 402 b within the contactlessconnector 300 allows for an overall compact structure of the contactlessconnector 300 since the non-conductive cover element 114, surroundingthe inner ferrite element 102, the inductive coupling element 110 andthe outer ferrite element 107, can be made thinner at the front portionof the connector in direction of the longitudinal axis L. In otherwords, the non-conductive cover element does no longer need to protectand/or encapsulate the antenna element 402 or 402 a as shown in FIG. 4or 7. Consequently, this arrangement allows for a reduced overhang ofthe non-conductive cover element 114 with respect to the front end ofthe inner ferrite element 103 and thereby improves the powertransmission efficiency between the inductive coupling element 110 ofthe contactless connector and the corresponding contactless connector inthe mated state.

To ensure efficient signal transmission by the antenna element 402b—arranged behind the inner and/or outer ferrite element 102, 107 withrespect to the mating end of the contactless connector 300—the antennaconfiguration of the contactless connector 300 additionally includes anantenna rod 1201 provided within the opening of the inner ferriteelement 102 of contactless connector 300 for forwarding electromagneticwaves between the mating end of the contactless connector 300 and theantenna element 402 b.

Specifically, the antenna rod 1201 has a conical shape where the frontside of the antenna rod 1201 (i.e. the side of the antenna rod 1201facing the mating end of the contactless connector 300) has a smallerdiameter than the opposite side of the antenna rod 1201. The lateraldimensions of the antenna rod 1201 are adapted to the inner diameter ofthe inner ferrite element 102. The tapered configuration of the antennarod 1201 allows for a radiating pattern of the antenna configurationwhich is focussed in the direction of the mating end of the contactlessconnector. Additionally, the surface of inner ferrite element 102 may beadapted to improve reflection the electromagnetic waves carried by theantenna element rod 1201 so as to act as a waveguide for the antennaelement 402 b.

Further, the antenna rod 1201 extends between the front end of the innerferrite element 103 and the rear end of the inner ferrite element 104.The antenna rod 1201 is also adapted to a wavelength of a carrierfrequency of the antenna element 402 b. In more detail, the length ofthe antenna rod 1201 corresponds to the carrier frequency according to apredefined ratio, e.g. integer multiples of the wavelength of thecarrier frequency. The antenna rod 1201 shown in FIG. 12 is suitable forcarrying radio waves with a carrier frequency approximately 60 GHz.

The antenna element 402 b is electrically connected to the electroniccircuit 401 including a transmitting/receiving circuit for wireless datatransfers. Additionally, the antenna element 402 b is arranged withinthe contactless connector 300 at close proximity to the inwardly facingside of the antenna rod 1201, specifically at a distance which allowsfor a highly efficient electromagnetic coupling between the antennaelement 402 b and the antenna rod 1201.

As can be readily appreciated from the description of the contactlessplug connectors above, the antenna configuration including the antennaelement 402 b and the antenna rod 1201 is an alternative to the antennaelement 402 as shown in FIG. 4 and the antenna element 402 a shown inFIG. 7. Accordingly, the above described antenna configuration, namelyincluding the antenna element 402 b and the antenna rod 1201, may alsobe incorporated into the contactless connector of the second embodiment,i.e. the embodiment including the bobbin 601.

For the contactless connector 100 of the second embodiment as shown e.g.in FIG. 7, instead of antenna element 402 a, the antenna element 402 bcan be arranged behind the inner and/or outer ferrite element 102, 107with respect to the mating end of the contactless connector. At the sametime, the antenna rod 1201 can be provided within the inner ferriteelement 102 such that it has a radiating pattern in the direction of themating end of the contactless connector. The antenna rod 1201 isconnected to the antenna element 402 b transmitting/receivingelectromagnetic waves via the mating end of the contactless connector.

References Reference Numerals Description 100, 300 Contactless connector101, 201 Mating end of the contactless connector 102, 202 Inner ferriteelement 103, 203 Front end of the inner ferrite element 104, 204 Rearend of the inner ferrite element 105, 205 Outer surface of the innerferrite element 106, 206 Hollow opening 107, 207 Outer ferrite element108, 208 Front end of the outer ferrite element 109, 209 Rear end of theouter ferrite element 110 Inductive coupling element 111, 211 Housingelement 112, 212 Front end of the housing element 200 Correspondingmating connector 113, 213 Rear end of the ferrite elements of thecontactless connector 114, 214 Non-conductive cover element 401Electronic circuit 402, 402a, 402b Antenna element 115, 215 Windings 216Magnetic field lines 217 Air gap 403 Thread 404 Coil power supply line501 Connector case 405 Potting 502 Connection interface 601 Inductivecoupling support element 602 Intermediate disc 603 Slot 604 Front disc701 Antenna connection line 702 Rear disc 801 Mounting pin 802a, 802bMetallic pins 1101  Openings of the rear disc 1201  Antenna rod LAxial/Longitudinal direction of contactless connector G Gap betweenhousing element 111a and rear end 113 of the ferrite elements inlongitudinal direction

The invention claimed is:
 1. A contactless connector for inductively connecting to a corresponding mating connector at a mating end of the contactless connector, the contactless connector comprising: an inner ferrite element; an inductive coupling element arranged to at least partially surround the inner ferrite element for transmitting or receiving power to or from the corresponding mating connector; an outer ferrite element arranged to at least partially surround the inductive coupling element along an axial length of the inductive coupling element, wherein a front end of the outer ferrite element facing the mating end is recessed such that the outer ferrite element is shorter than the length of the inner ferrite element in an axial direction of the contactless connector with respect to a front end of the inner ferrite element facing the mating end, and wherein a rear end of the outer ferrite element is magnetically connected to a rear end of the inner ferrite element; and an inductive coupling support element arranged around the inner ferrite element; wherein said inductive coupling element is a wire wound to form a coil comprising a plurality of coil windings that are wound around the inductive coupling support element; wherein said inductive coupling support element comprises an outwardly extending intermediate disc that divides the coil windings into a first coil winding section and a second coil winding section; wherein the intermediate disc has a slot forming a coil wire passageway through which the coil wire is routed; and wherein the coil comprises more winding layers in a first section at a front part of the inner ferrite element that is not surrounded by the outer ferrite element than in a second section at a rear part of the inner ferrite element that is surrounded by the outer ferrite element.
 2. The contactless connector according to claim 1, the inductive coupling element is radially arranged around the inductive coupling support element.
 3. The contactless connector according to claim 1, wherein the coil comprises an even number of layers in the first and second sections.
 4. The contactless connector according to claim 1, further comprising a non-conductive cover element arranged to surround the inner ferrite element, the inductive coupling element and at least part of the outer ferrite element.
 5. The contactless connector according to claim 4, wherein the non-conductive cover element is overmolded.
 6. The contactless connector according to claim 1, further comprising a housing element which is spaced from the rear end of the outer ferrite element by a predetermined distance with regard to the axial direction of the contactless connector.
 7. The contactless connector according to claim 1, further comprising at least one antenna element.
 8. The contactless connector according to claim 7, further comprising an antenna connection line for connecting the antenna element, wherein the antenna connection line is routed through the ferrite element.
 9. A contactless connector system comprising a contactless connector according to claim 1, and a corresponding mating connector connected to the contactless connector such that the contactless connector allows for transmitting/receiving power to/from the corresponding mating connector.
 10. A method for manufacturing a contactless connector, the method comprising the steps of: providing an inductive coupling support element comprising an outwardly extending intermediate disc having a slot; arranging an inductive coupling element around the inductive coupling support element by winding a wire to form a coil comprising a plurality of coil windings that are wound around the inductive coupling support element into a first coil winding section and a second coil winding section; inserting an inner ferrite element into a recess of the inductive coupling support element; and enclosing, by an outer ferrite element, at least a part of the inductive coupling element, which is arranged around the inductive coupling support element, wherein a front end of the outer ferrite element facing the mating end is recessed such that the outer ferrite element is shorter than the length of the inner ferrite element in an axial direction of the contactless connector with respect to a front end of the inner ferrite element facing the mating end; providing more winding layers in a first section at a front part of the inner ferrite element that is not surrounded by the outer ferrite element than in a second section at a rear part of the inner ferrite element that is surrounded by the outer ferrite element; wherein the method further comprises the step of routing the coil wire through the slot while forming the coil winding sections.
 11. The method according to claim 10, further comprising the steps of: providing an antenna element within the contactless connector; and providing a non-conductive cover element so as to surround the inductive coupling support element, the inductive coupling element, the inner ferrite element, the outer ferrite element, and the antenna element. 